Orbital floor grinders typically include an electric motor having an output shaft that extends through a drum assembly. The output shaft drives a belt that drives a plurality of treatment disks that contact the flooring surface. To improve handling of the machine and the treatment effects to the flooring, the orbital machine is typically configured to counter-rotate the drum housing relative to the direction of rotation of at least some of the treatment disks.
The present disclosure relates to an improved configuration for rotating the drum assembly that avoids the need for a separate traveling belt for rotating the drum assembly.